An accurate determination of velocity is critical in order to navigate objects such as projectiles and missiles to a desired point in space. Existing systems and methods often use a GPS receiver to determine velocity. However, GPS systems add to the cost of producing projectiles and missiles. In addition, many projectiles and/or missiles are used in applications where the mission timelines are too short to use GPS.
When GPS or other direct means of measurement (i.e., pressure transducer, Doppler radar) are unavailable or undesirable for whatever reason, the initial velocity must be estimated in order to properly operate a guidance system that navigates the object. One method of estimating the initial velocity of a projectile or missile is to characterize the launch velocity versus the temperature of the object's propellant charge and/or the launch chamber pressure.
Accurately estimating the velocity is crucial in applications where precise navigation is required for long range target engagements with objects such as guided projectiles, bombs and missiles. One of the drawbacks with existing systems and methods that estimate velocity is that the accuracy of these estimates often suffers due to external considerations that cannot be accounted for during actual operation of the object. As an example, many known projectiles typically have a substantial variation in propellant characteristics from round to round. This variation usually causes high variability in exit tube velocity (i.e., up to 10 m/s).